"(It's) always a reminder to me and my family of what is important," Cyrus added. "Never let success change your heart."

The admiration is certainly mutual. In a 2012 interview with country music publication The Boot, Parton called Cyrus "a little Elvis" and a "fantastic singer and songwriter."

Parton and Cyrus have shared some great moments over the years. Parton guest-starred on "Hannah Montana," the Disney show which launched Cyrus' career more than a decade ago, and the pair sang Parton's classic hit "Jolene" in a powerful performance on "The Voice" in 2016.

Other celebrities honored Parton's birthday by sharing similar sentiments on social media.

"Few people in this world have touched my heart like Dolly," wrote actress and producer Reese Witherspoon on Twitter. "She has been my inspiration all my life. A beautiful spirit."

Witherspoon even promised to donate the day's sales of her clothing line, Draper James, to Parton's charity, an international children's book gifting program.

Beautiful, talented, confident, amazing, generous...BIRTHDAY GIRL!!! Love you @DollyParton !!! You inspire everyone who is blessed enough to be around you! I hope you have an amazing birthday! Hope to see you soon! pic.twitter.com/DZq3UbWEKO

"Beautiful, talented, confident, amazing, generous ... BIRTHDAY GIRL!!!" country singer Carrie Underwood wrote on Twitter. "Love you @DollyParton !!! You inspire everyone who is blessed enough to be around you! I hope you have an amazing birthday! Hope to see you soon!"

It's heartening to see the impact Parton has made on those around her, and even better to see good things coming back her way. Happy birthday, Dolly!